Timing device



Dec. 14, 1948. E, PETERSON I 2,456,018

TIMING DEVICE Filed June ze, 1944 A 2 sheets-sheet 1 INVENTOR. 3 EDWARD S. PETERSON ATTORN EY Dec. 14, 1948. E, s. PETERSON 2,456,018

' TIMING DEVICE Filed June 26, 1944 2 Sheets-Sheet 2 sf* [J flo 3 .TIMING oEvlcE -soLENolD qon. f l c c ,5/A 1 soLeNmn T PLUNGER `TERMINALS FIG, e

' INVENTOR.

5 EDWARD S. PETERSON ATTORNEY Patented Dec. 14, 1948 TIMING DEVICE Edward S. Peterson, Elmwood Park, Ill., assigner to Automatic Electric Laboratories, Inc., Chicago, Ill., a corporation of Delaware Application June 2,6, 1944, Serial No. 542,178

1 Claim. 1

The present invention relates to timing devices in general, and more particularly to a new and improved timing device for electrical circuits which is economical in operation, highly accurate, shock proof, unaffected by temperature conditions, and non-positional in mounting characteristics.

One object of the invention is to provide a timing device that is non-stallable in any position. Such a device is particularly adapted for use on aircraft, ships and other like applications where plumb and level conditions are not stable. There are also many other application requirements which necessitate mounting the timing device in the position best suited for the individual application.

Another object of the invention is to provide accurate timing through the media of new and novel means of associating a clockwork mechanism with a solenoid control, the particular arrangement including means for causing switch contacts to be operated after a predetermined interval of time has been accurately timed by the clockwork mechanism.

A further object of the invention is to provide mined interval of time. No change is made in the f position of switch contacts under such conditions until the clockwork mechanism has operated for the full predetermined interval of time, irrespective of the number of incomplete attempts made by the clockwork mechanism.

Another obj ect of the invention is to operate the timing device economically. As is well known, a solenoid requires considerably more power for its energization than is required to maintain the solenoid in the energized, or holding, position. The invention, therefore, includes means for reducing the current flow through the coil of the solenoid after the coil is fully energized and until the circuit of the coil is broken. Consequently, a saving in current consumption is effected when the holding periods of the solenoid are of longer duration than the time required to energize the solenoid, such a situation prevailing in many cases.

In order to accomplish the above described objects, the timing device consists essentially of a clockwork mechanism for accurately timing a predetermined interval of time, new and novel means controlled by a solenoid for causing the clockwork mechanism to operate for the predetermined interval, and means for operating switch contacts after the clockwork mechanism has completed the timing.

A feature of the invention is that the timing device is universal in mounting application and, consequently, may be mounted in the position best adapted for each particular installation. This non-positional mounting feature is made possible by the particular design of the coupling between the clockwork mechanism and the plunger of the solenoid, this coupling being self-aligning under all conditions and employing no links, guides or other mechanical devices which may be affected by gravity in relationship to the particular mounting position, or become jammed as a result of unnatural strains.

Another feature of the invention is that the coupling between the clockwork mechanism and the plunger of the solenoid includes an arbor so connected with both units that the solenoid plunger, as it is drawn into the coil of the solenoid, correspondingly turns the arbor to tension a power spring, and, when the circuit of the solenoid coil is opened, the tensioned power spring causes the arbor to turn in the opposite direction for driving the clockwork mechanism and for gradually withdrawing the plunger until the plunger reaches a stop limiting its outward movement. the clockwork mechanism regulating the speed of withdrawal. A simple and positive action for setting the clockwork mechanism is thus assured without requiring complicated adjustments or lubrication. The coupling arrangement also ermits the solenoid to reset the clockwork mechanism at any instant before the clockwork mechanism has operated for the full predetermined interval of time.

Another feature of the invention is that means is provided for so adjusting the normal tension of the power spring that the drawing in of the solenoid plunger responsive to the energization of the solenoid coil will properly tension the power spring for driving the clockwork mechanism and withdrawing the plunger from the solenoid coil when the circuit of the solenoid coil is opened.

Another feature of the invention is that the length of the interval timed by the clockwork mechanism may be adjusted to suit the requirements of each particular installation. Adjustments are made by changing the position of the lever operating the switch contacts.

Another feature of the invention is` that the switch operated by the timing device may be of either the snap action (quick break and/or make) type or of the well known telephone relay contact spring type, and may be fitted with single or multiple poles and be single or double throw.

Another feature of the invention is that economical operation of the timing device is achieved through the use of a resistor which is switched in series with the coil of the solenoid when the solenoid is in the energized position. The reduction of current consumption during the periods that the solenoid' is held inthe energized* position represents a direct saving because in many timing installations the holding periods are longer than.

the time required to energize the solenoid coil.

There are other objects and features of."the.l

invention having to do for the most part with the circuit and mechanical'd'etails involved., in'

carrying out the foregoing. The various objects and features of the invention will be understood best upon a further perusal of tlrerdescription in connection with the accompanying drawing-s.

The invention is disclosed in two sheets of drawings comprising Figs. 1 to 6, inclusive. Fig. 1 is a side view of the timing. device, in elevation,

showing the general relationship -oi the solenoid" coil', solenoid plunger, arbor, andv clockwork mechanism, also. illustrating. the attachment of va power spring between the arbor and an adjustable bracket mounted on. the base plate supporting. the solenoid structure; Fig. 2 is a top view of the device, in elevation, showing the general arrangement of. the switches with respect to the. arbor andi its associated members for operating the switches.; Fig. 3 is a side View, in elevation, opposite to theview shown in. Fig.. l andfshows means. for adjusting the `outward movement oi the solenoid plunger and also the location of the resistance coil wired'in series with the coil of thev solenoid; Fig.. 4 is apartial top View, in elevation, iorillustrating how a snap actionicluick breakl and/or maker) type of switch, such as thev well known cantilever midget power switch, may be employed. in` place. of the conventional relay contact spring.y assembly shown in. 2;, Fig. 5v isan enlarged sectionalviewl looking down on. the solenoid plunger meshed with its associated. gearl wheel mountedl on the arbor, this View alsoy showing the attachment oi the power` spr-ing to a. plate member of the arbor; and d diagrammatically illustrates.v

the general circuit` arrangement in association with the major apparatus units.

Reierringnow to Figs.. 1 to 6, inclusive, a de-A tailed descriptionA wil-l be.A given oi the mechanical arr-'angementv oi the: timing, device, after' which williollow a description'. of the operation.

They timing device consists essentially of a switch l connected in the circuit oi a given application in which a. predetermined time delay is required beiore the operation of switch l changes the circuit conditions it controls,y a rotating .arbor 2r withan associated member' 3 for operating switch I, av solenoid coil Ef controlling the movement-of a plunger: 'I gear coupl-ed to arbor 2, a power spring II attached to a circular plate member I?. of arbor 2., andla clockwork mechanism t7- coupled-toarbor 2..through the medium of .a ratchet device I4.v When the. circuit of solenoid. coil .SG is closed. by means of a control circuit, plunger 'I'is drawn quickly` into the solenoid 6. and correspondingly rotates arbor 2.

through a given. are by. means of gear coupling I2. This rotation. oi arbor 2 tensions power spring. I I. through thenredium. of a .plate member I3, and also movesmember 3. from switch I. When solenoid coil is deenergized by the opening of the control circuit, power spring I I causes the rotation of arbor 2 in the opposite direction because plunger I is no longer held by magnetic attraction and, consequently, plunger 'l is withdrawn from solenoid coil 6 through the medium of gear coupling E2. The withdrawal of plunger i is gradual instead of instantaneous because ratchet I4 now couples the clockwork mechanism il iixedly, with arbor 2 with the result that the clockwork mechanism I'I' controls the return movement of arbor 2. Hence, member 3 will not reach and operate switch l until the clockwork mechanism has operated for the predetermined tin-re interval.

It should-beunderstood at this time that the timing device arrangement outlined in the precedingparagraph is but one embodiment of the invention, and that various changes or modications'may' be carried out to accomplish desired arrangements, as will be apparent to those skilled in the art. It is also obvious that the time delay may be usedv for retarding the magnetic attraction. oi the plunger instead oi" delaying the outward. movement of the plunger.

The length oi .time the clockwork mechanism il is permitted to operate by spring power when solenoid. coil l5. is deenergized, is controlled by fitting the clockwork mechanism with the proper gear trainto establish thedesired time interval. Supplementary adjustment may be made by adjusting the stop 2l which limits the outward movement ci plunger l. The plunger stop arrangement is illustratedin Fig. 3 and. also in the enlarged sectional view oi Fig. 5. Bracket 20 attached to the mounting plate supporting switch l provides hrm anchorage for stopy screw2.l, and.

nut 22 locks the stop screw in place.

The arbor 2 includes an upper shaft and a lower shaft, the lower sha-ft being. partly tele.- scoped within the upper shaftand coupled thereto byrneansoi ratchet I4. The telescoping is do-ne on a loose fit basis so that the upper shaft serves as one-bearing for the lower shaft, and vice versa. A. second bearin'gyfor each` shaft is included respectively in the upper and lower mounting plates supporting, the. solenoid structure. The toothedwheel of ratchet I4 is attached solidly to a hub of the lower shaft, and. the pawl of ratchet I4 isattachedto arplatemember I3. of the upper shaft andl kept in contact withthe toothed wheel.

workniechanism- I7., and. the. upper. shaft carries a member 3 for operating switch-I. The purpose of ratchet I4- is tov permit. slippage between the upper and lower shafts when. the upper shaft is.

caused. to rotate by means of the gear coupling I2 as plunger 'I is movedv inward by magnetic attraction, andv to lixedly couple the upper and lower shafts together whenthe upper shaft is rotated in the opposite direction by power spring. II so that bothshafts. then rotate as one. unit. The clockwork mechanism I'Iv is, therefore, operated only when ratchet I4 transmits. the4 energy of power spring I I. from the upper shaft tothe lower shaft..

Itis. of particular interest. that the coupling meansbetween solenoid plunger 'I, arbor 2 with its two shafts and. ratchet. I4, and clockwork mechanismv I.1. is self-aligning at all times, and. includes no. links, guides-` or other similar devices. which may be affected. by gravity if the mounting posi.- tion. withrespectto. plumb and. level conditions is notmaintained. It should be understood, however, that other well known methods of coupling two shafts together so that only one shaft rotates when the rotation is in one direction and both shafts rotate as one unit when the rotation is in the opposite direction, are equally as adaptable as the particular coupling just described.

One end of the power spring II is attached to plate member I3 of the upper shaft of arbor 2, and the other end to an adjustable bracket I8, as shown in Fig. 1. The adjustable bracket I6 is slotted in order that it may be moved forward or backward lengthwise on the lower mounting plate I5 supporting the solenoid structure, thus permitting the normal tension of spring II to be correspondingly decreased or increased. Screws are provided for securing bracket I6 in the adjusted position. The driving tension for spring II is obtained when arbor 2 is rotated clockwise (looking at the top view of Fig. 2) by the magnetic attraction of plunger 'I. The normal tension is so adjusted that the maximum driving tension will not overcome the magnetic attraction of plunger 1.

The time interval required for arbor 2 to move member 3 into mechanical contact with switch I after solenoid coil 6 is deenergized, may be varied by changing the position of member 3 on arbor 2, a locking means I9 (Fig. 1) permitting the loosening and fixing of member 3. Moving member 3 in the direction of switch i will shorten the time interval and, conversely, moving member 3 in the direction away from switch I will increase the time interval.

The blades of switch I shown in Fig. 2 are of the well known relay twin contact spring type. The particular combination illustrated is double pole double throw, but it is obvious that any desired contact combination may be provided in either single pole or multiple pole. The speed of the switch contact operation with this type ofcontact spring is determined by the speed of travel of member 3 under the control of clockwork mechanism I1, the contact movement being relatively slow or rapid as the case may be. When circumstances require switch contactsv with snap action (quick break and/or make), switch I may be any suitable well known snap switch, such as, for example, the cantilever type of midget power switch illustrated in Fig. 4.

Resistor 8, the location of which is shown in Figs. 2 and 3, is provided for the purpose of reducing the current flow through solenoid coil 6 after solenoid coil 6 is fully energized and for the subsequent period solenoid coi] 6 remains energized. It is a well known fact that a solenoid lcoil requires considerably more power to attract a plunger magnetically than is required to maintain the plunger in the attracted position. A saving in current consumption is, therefore, accomplished by increasing the resistance value of the solenoid coil circuit during the periods the plunger is in the attracted position, when such holding periods are longer than the time required to attract the plunger, which situation is prevalent in many timing applications. Resistor 8 is wired in series With solenoid coil 8 but is normally shunted by the contacts of switch 5, as shown in Fig. 6. When solenoid coil 6 is energized and attracts plunger 'I, member 4 attached to arbor 2, as shown in Fig. 2, is moved towards switch 5, and reaches and operates switch 5 just before plunger 'I reaches its innermost position. The operation of switch 5 removes the shunt from resistor 8, and the resistance value of the circuit of solenoid coil 6 is increased by the resistance value of resistor 8, thereby reducing the current ow through solenoid coil 6. When the circuit of solenoid coil 6 is opened, member 4 is moved away from switch 5 by arbor 2, and the closing of the contacts of switch 5 re-establishes the shunt around resistor 8 and thereby decreases the resistance value of the energizing circuit of solenoid coil 6 to normal.

While Fig. 6 indicates that switch 5 is used for the purpose of reducing the current flow through solenoid coil 6 when plunger 'I is fully attracted, it should be understood that switch 5 may be fitted with any desired contact arrangement and used for performing other switching operations associated with the timing application. Thus it is possible to construct the timing device to operate switch 5 when solenoid plunger 'I is magnetically attracted, this operation being practically instantaneous, and then operate switch I after a desired interval of time has lapsed, as controlled by clockwork mechanism I I, both switches controlling switching operations associated with the timing application. It is also possible to reverse the time delaying operation so that switch 5 is not operated until the predetermined interval of time has lapsed and then operate switch I immediately after the circuit oi solenoid coil 6 is opened.

In view of the foregoing description it is believed that the invention can be most readily made clear by describing its mode of operation in a typical application.

Referring now to Fig. 6, it will be assumed that the particular installation includes a contact switch IIJ which is closed and opened at certain intervals for controlling the operation of the timing device, and a source of power supply 9 wired in series with solenoid coil 6 of the timing device and contact switch Ill. Also, the circuits to be controlled by the timing device require that switch I be tted with double-pole double-throw contact blades as shown. The circuits to be controlled by the timing device are connected to terminals 23 shown in Figs. l, 2 and 3, the terminals 23 being wired to the contact blades of switch I. Solenoid plunger 'I is coupled to arbor 2 in the manner previously described so that member 3 attached to arbor 2 is normally in mechanical contact with switch I, and member 4 attached to arbor 2 is normally away from switch 5.

The closing of contact switch II) connects power source 9 to solenoid coil 6 and, since resistor 8 is shunted by the contacts of switch 5, solenoid coil 6 magnetically attracts plunger 'I. The inward movement of plunger I causes arbor 2 to rotate in a clockwise arc for moving member 3 from mechanical contact with switch I and for causing member 4 to operate switch 5, these oper-- ations requiring very little time. The removal of member 3 from switch I permits switch I to operate by its own spring power to break its normally closed contacts and make its normally open contacts for accomplishing certain circuit changes in the timing installation. The operation of switch 5 by member 4 occurs just before plunger 'I has completed its inward movement and opens the shunt across resistor 8, which action correspondingly increases the resistance of the circuit of solenoid coil 6 and thus reduces the current consumption of solenoid coil 6. The inward movement of plunger 'I by magnetic attraction also causes arbor 2 to tension power spring I I (shown in Fig. 1) to provide power for rotating arbor 2 in the opposite direction when plunger 'I is freed from magnetic attraction, and for driving clockwork mechanism I'I during the return movement of arbor 2.

2,45egois The plunger 'l is retained in the attracted position until contact switch Ifof the timing installation is operated to open the circuit of solenoid coil l6. When the circuit of solenoid coil 6 is opened, plunger is freed 4from further magnetic attraction and, consequently, power lspring Il (shown in Fig. 1) overcomes the inertia o plunger l and starts the rotation of 'the upper shaft of arbor 2 in the reverse-direction. Immediately the upper shaft of arbor 2 starts to rotate inthe reverse direction, ratchet I4 (Figs. 1 and 3) xedly connects the upper and lower shafts of arbor 2 together so that both shafts will rotate as-one unit. Hence, power spring H drivesclockwork mechanism Il through the combination of the upper shaft or" arbor 2, ratchet i4, and the lower shaft of arbor 2. Arbor 2 can, therefore, rotate on its return movement only at the rate of speed permitted by the gear ratio of clockwork mechanism l'l.

The return movement of arbor 2 accomplishes several results as follows:

1. The moving of member 4 from mechanical contact with switch 5, thus permitting switch 5 to close its contacts for again shunting resistor 8 and thereby restoring the original resistance condition to the circuit of solenoid coil 6. This action occurs almost immediately when the return movement of arbor 2 is started, the exact time required being dependent upon the speed of the return movement as regulated by lclockwork mechanism l1. The position of member 4 on the upper shaft of arbor 2 maybe changed to Vary the point at which switch 5 is contacted and freed, locking means I8 (Fig, 1) permitting the loosening and xing of member 4.

2. The gradual moving of member 3 towards switch I until member 3 operates switch l, as regulated by clockwork mechanism l1. Member 3y reaches and operates switch l lat the expiration of a certain predetermined interval of time after the opening of the circuit of solenoid kcoil by contact switch l0.

3. The gradual withdrawal of plunger I from solenoid coil 6 until the outer end of plunger l J7 reaches stop 2| (Figs. 3 and 5). Plunger 'l reaches stop `2| at the expiration of the interval of time clockwork mechanism l1 is to be permitted to operate. The interval of time clockwork mechanisrn l1 is permitted to operate continues until member 3 has operated switch l. When member 3 has `operated switch l, plunger 1 reaches stop 2l, this action preventing further movement of arbor 2 and clockwork mechanism l1.

4. The operation of switch I by member 3 restores the circuits of the timing installation controlled by the timing device to the original arrangement prevailing at the time the circuit of solenoid coil 6 was closed by power switch I0.

What is claimed ist In a timing mechanism, the combination of a solenoid having a plunger, an adjustable stop for providing an outward plunger movement of deu sired length, means for energizing and deenergizing said solenoid at certain intervals, a switch for controlling an electric circuit or circuits, a gear train, a spring, rotatable means, said plunger drawn into said solenoid by the energization of said solenoid for causing one 4operation of said rotatable means to tension said spring, said tensioned spring responsive to the deenergization oi said solenoid causing another operation of said rotatable means to move said plunger outwardly to said stop, means for coupling said gear train with said plunger only when said plunger is moved outwardly to delay said plunger reaching said stop for a denite period of time, the arresting of said outward movement of said plunger causing the operation of said switch providing that said plunger reaches said stop before said solenoid is again energized andaga'in attracts said plunger, the ire-attraction of said plunger before said plunger reaches said stop preventing the operation of said switch, causing said coupling means to be temporarily disconnected from said gear train, and causing said rotatable means to retension said spring.

EDWARD S. PETERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 835,025 Jackson Nov. 6, 1906 877,144 Vogelsang Jan. 21, 1908 935,733 Beri'esford Oct. 5, 1909 1,004,383 Davis Sept. 26, 1911 1,017,246 Calderwood Feb. 13, 1912 1,421,157 Bouton June 27, 1922 1,575,536 Bunting Mar. 2, 1926 

